System for detecting partial discharge direction of compound eye type optical fiber EFPI

Abstract

The invention relates to a system for detecting the partial discharge direction of a compound eye type optical fiber EFPI and belongs to the technical field of online monitoring of partial discharge of electric power paper oil insulation electrical equipment. A narrow-band light source (1), an optical filter (2) and an optical splitter (3) of the system are sequentially connected; an optical circulator, a single mode optical fiber and an optical fiber external cavity type Fabry-Perot sensing head of each of five light paths obtained through splitting are sequentially connected; each optical circulator is further connected with a photoelectric detector (7) and an amplifier (8); the amplifiers (8) are connected with an oscilloscope (9). Power is supplied, so that all the devices are in the working state; a compound eye type optical fiber external cavity type Fabry-Perot sensor is placed at the top end of an insulating rod, and the insulating rod is rotated till the partial discharge pulse amplitude of the optical fiber external cavity type Fabry-Perot sensing head located in the middle is the largest but the partial discharge pulse amplitudes of the other four optical fiber external cavity type Fabry-Perot sensing heads are roughly equal; then, the orientation of the optical fiber external cavity type Fabry-Perot sensing head located in the middle is the direction of the partial discharge point. The system is high in sensitivity, good in directivity and high in anti-interference capacity and can be used for locating the partial discharge direction of key portions of electrical equipment conveniently and accurately.

Description

technical field [0001] The invention relates to a compound-eye optical fiber EFPI partial discharge direction detection system, which belongs to the technical field of on-line partial discharge monitoring of electric oil-paper insulated electrical equipment. Background technique [0002] At present, there are many methods for on-line partial discharge monitoring of oil-paper insulated electrical equipment (mainly transformers) at home and abroad, mainly including very high frequency (VHF) pulse current detection method, ultra high frequency (UHF) electromagnetic wave detection method and piezoelectric sensor ultrasonic detection method Among them, the VHF and UHF detection methods detect electrical signals, which are easily interfered by electromagnetic interference signals; the piezoelectric ultrasonic method detects ultrasonic signals, but the sensor is attached to the device shell to detect the ultrasonic signals generated by partial discharge inside the device. Although ...

AI Technical Summary

Problems solved by technology

The sensitivity of the Michelson method detection system is not high, and there is a multi-path problem in ultrasonic propagation; the demodulation frequency response of the optical fiber Mach-Zehnder interferometry is not high enough, the structure is complex, and the requirements for equipment are high; the optical fiber Fabry-Perot law has The advantages of simple structure, small size, high reliability, high sensit

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